Reed dent arrangement

ABSTRACT

The disclosure is directed to a reed dent arrangement for a wave-motion loom in which the reed dents are arranged between laminar guide elements, have elongate, lamella-like shape, and travel at a narrow side on drive-cam means which imparts to them pivoting or rocking movements taking place about an axis extending perpendicular to their broad sides.

1451 Aug. 19, 1975 Strauss REED DENT ARRANGEMENT 3,739,816 6/1973Kramenic et a1. 139/12 5 1974 l [75] Inventor: Edgar Strauss, Ruti,Zurich, 3809l30 Strauss et a 89/12 Switzerland [73] Assignee: RutiMachinery Works Ltd., Ruti, Primary Examiner1-1enry S. jaudon Zurich,Switzerland Attorney, Agent, or Firm-Donald D. Denton [22] Filed: Jan.28, 1974 [21] Appl. No.: 436,866

[57] ABSTRACT [30] Foreign Application Priority Data Feb. 2, 1973Switzerland 1540 73 The disclosure is directed to a feed dentarrangement for a wave-motion loom in which the reed dents are 52 U.S.C1 139/12; 139/192 arranged between laminar guide elements, have [51Int. C1. D03D 47/26 gate, lamena'like shape, and travel at a narrow Side58 Field 61 Search 139 12, 13, 16, 66 A, 79, drive-Cam means whichimparts t9 them p g 9r 139/82 74/569 rocking movements taking placeabout an axis extending perpendicular to their broad sides. [56]References Cited UNITED STATES PATENTS 8 Claims, 8 Drawing Figures3,124,164 3/1964 Ewing 139/12 PATENTEU AUG 1 91975 2x 20 23 27 Fl {f7 II a) Fig.5 77

Q i A W REED DENT ARRANGEMENT BACKGROUND OF THE INVENTION In looms ofthe wave-motion type, the reed dents serve not only for beating up theweft threads but also for driving the shuttles. They drive the shuttlesdue to forces directed transversely of the broad side of the reed dents.If the drive camming means is constituted by a screw-shaft, then alsothis component affords, due to its helical pitch, a thrust forcedirected transversely of the broad side of the lamella-shaped reeddents. In order to prevent lateral compression (condensing) of the reeddents on mutual contact taking place, i.e. in order to prevent the reeddents from being crowded together due to the thrust force along the axistowards one side of the loom, and thereby pressed together, they arearranged between laminar guide elements and effect their rockingmovement in thin interspaces provided between each two adjacent guideelements. In order that the reed dents may be as mobile as possible, theinterspace is so dimensioned that some free space or a slight lateralclearance is available between the reed dent and the guide elements. Itis a further important task of the guide elements to effect thesupporting of the pivot about which the reed dents are rockable.

It has now been found that, due to the thinness of the reed dents(determined by textile requirements), incisions may be formed both inthe pivot of the reed dents and also in the drive means for the latter.The drive means are preferably designed as screw-shafts provided withproviles made from a plastics material. In the case of these, it mayadditionally happen that the plastics is displaced laterally of theincisions formed.

Due to these circumstances and effects, the attempt might be made todesign the reed dents to be thickened, to the extent that this ispossible textile-wise. Thereby, the reed dents would, in the zone of thethickened dents portions, be layered one against the other withoutinterspace. With this solution, however, it would no longer be possibleto arrange guide elements between the reed dents. For reasons alreadymentioned, i.e. the condensing or crowding together of the reed dents,and also the provision of a carrier for the pivoting axis, it isindispensable to provide a guide element between each dent.

The closest prior art known to the applicant in connection with theinvention presented in this application for Letters Patent is in BritishPatent No. 1,201,295.

SUMMARY These disadvantages are to be obviated by the pres entinvention. The invention is characterized in that each reed dent has, atleast at one of the locations at which it bears on the drive cammingmeans or on the pivot, a thickened portion. It will be appreciated thatthe above and other advantages will be apparent from the followingdescription of the invention which will be discussed in greater detailwith reference to examples of embodiments and with reference to thedrawings, in

which:

FIG. I shows a cross-sectional view illustrating the reed dents and theassembly thereof with the remaining elements;

FIG. 2 is a plan view of the elements shown in FIG. 1 showing theprofile of the driving earns;

FIG. 3 is a cross-sectional view taken along the line III-III of FIG. 1showing reed dents with thickened portions;

FIG. 4 is a cross-sectional view along the line lV-IV of FIG. 1 showingthe thickened portion of the reed dents;

FIG. 5 shows a reed dent according to the invention, as seen from theside, i.e. as viewed towards one of its broad sides;

FIG. 6 shows an elevational view of the reed dent according to FIG. 5 asviewed towards one of its narrow sides;

FIG. 7 shows a lateral view of a further embodiment of a reed dent; and

FIG. 8 a through d shows some examples of various types of thickenedportions for reed dents.

DESCRIPTION OF PREFERRED EMBODIMENTS FIG. 1 shows two end positions of areed dent 11, one depicted in black lines. The reed dent 11 is pivotalabout a pivot axis 12. FIG. 2 shows how the reed dents 11 are alignedalong the pivot axis 12. Each reed dent 11 is arranged between two guideelements 13. Two screw-shafts 14 have a profile so shaped that bothscrew-shafts 14 continuously bear at each reed dent 11. The profile ofeach screw-shaft 14 thus constitutes for each reed dent 11 a drive cam,whereby the reed dents are induced to perform pivoting or rockingmovements, the direction of which is shown by the double headed arrow15. The entire assembly of guide elements 13 and reed dents 11 with thepivot 12 is combined by rods 16 (only two thereof shown in FIG. 2) toconstitute an assembly secured to the loom. The pivot 12 extends throughthe guide elements 13 in the direction perpendicular to the latter andis disposed in apertures formed in the latter. It is supported by theguide elements 13. FIG. 1 also shows shaft healds 17 by means of whichsheds are formed from the warp threads 18. The woven fabric produced bythe operation of the read dent arrangement has been designated 19.

FIG. 3 illustrates a cross-sectional view at the location designatedIIIIII in FIG. 1. The reed dents 11 have thickened portions 20 extendingalong the periphery of the pivot 12 over that zone via which the reeddents 11 bear on the pivot 12. The guide elements 13 are formed withapertures 26 by means of which spaced is provided for the thickenedportions 20, without the guiding of the reed dents 11 being therebyhindered by the elements 13. FIG. 4 (which is a cross-section atlocation IV-IV of FIG. 1) shows that the reed dents have furthermore athickened portion 21 at that location at which they bear on theright-hand screw-shaft 14 in FIG. 1. In the case of the left-hand screwshaft 14 according to FIG. 1, there is a further corresponding thickenedportion 21. The design of the reed dents 11 is best seen from FIGS. 5and 6. Due to the provision of the thickened portions 20 and 21, theformation of incisions both in the pivot 12 and also in the drivecamming means 14 is prevented or at least very considerably reduced,Without its being necessary to accept the disadvantages resulting fromthickened reed dents ll.

Hitherto, it had been necessary to impart a certain degree of widthenlargement to the reed dent according to FIG. 5, so as to secure itagainst tilting or tipping. According to the example shown, thethickened portions 20 are so selected that they are able to contact eachother with only a small clearance or play. Therewith also, the danger oftilting is eliminated, so that the aforementioned width enlargement" ofthe reed dents 11 is no longer necessary. Thus, it is possible to employreed dents 22 such as have the narrower shape shown in FIG. 7. Thesehave the important advantage that the pivot 12 no longer requires to bepushed through a closed aperture in the read dent 22, since the latteris downwardly open at its pivot-point. This has again the advantage ofextremely ready replaceability and also lower reed dent weight.

The thickened portions 20, 21 may be of varying shapes and sizes. Theymay, for example as shown in FIG. 8a with regard to the thickenedportion 20, be constituted by strips which are hard-brazed onto the bodyof the reed dent. Of course, it is possible to employ also such awelded-on strip for the thickened portions 21. On punching out thelaminar reed dents, it will be possible to leave standing a projectingstrip 23 which is bent over, thus affording'a shape according to FIG.8b. The embodiment shown in FIG. 80 is suitable for the thickenedportions and 21. It is manufactured in a pressing step and can beemployed in particular in the case of reed dents made from plastics.Referring to FIG. 8d, the thickened portion comprises a U-shaped stripapplied along a longitudinal edge of the reed dent 11. In particular incases wherein the thickened portion 21 is made from plastics, thisembodiment is suitable also for the thickened portion 20.

In operation of the loom, the rocking movements of the reed dents 1]follow each other, one after the other, in the sequence of theirarrangement along the pivot 12. The pivoting of two adjacent reed dentsrelativev to each other is always relatively small. However, it isnecessary to ensure that, in the case of the embodiments according toFIGS. 8b, c, d, the thickened portion 21 of one of the reed dents alwaysremains in lateral abutment against the adjacent reed dent 11 at leastover a small zone, in order to exclude any possibility of jamming orimpingement of a thickened portion with its adjacent reed dent. In thecase of the embodiment according to 8d, it is correspondingly necessarythat, in all pivoting positions, the adjacent thickened portions 21should remain continuously in lateral abutment. In order that this maybe the case, the maximal, mutual pivoting or rocking of immediatelyadjacent reed dents *11 at the location of the end adjacent the pivot 12of a thickened portion 21 must, as to length, be smaller than the widthof the thickened portion 21.

In connection with the showing in FIG. 4, it should also be pointed outthat the maximum forces at the reed dents 11 occur during weft beat-up.This is the case when the reed dents 11 travel on the highest portion ofthe screw-shaft 14. It will be perceived that, under thesecircumstances, the thickened portions 21 bear flat at their broad sideon the surface of the screw shaft 14, so that the pressure per surfaceunit remains at a low level. Additionally, relatively large forces occurat the commencement of acceleration of the ends of the reed dents 11projecting out of the guide element 13 assembly, in the upwarddirection. This is the case approximately at the location 24. Thereagain, the thickened portions 21 bear more or less parallel to thesurface of the screw-shaft 14.

If the shape illustrated of the reed dents is compared with thepossibility, mentioned at the outset, for utiliz- 4 ing generallythicker reed dents, then it will be apparent that the constructionaccording to the present invention has, additionally, the advantage thatdue to the interspaces available between the reed dents 11 and the guideelements 13 fibers which fly about" are not readily caught up and ifsome should be so caught up they can be blown away or they areautomatically eliminated.

Diminution of wear or formation of incisions is achieved if, at least atone location at which the reed dents 11 bear on the drive camming means14 or on the pivot 12, a thickened portion 21 or 20 is provided.

It will be appreciated that various changes and modifications may bemade within the skill of the art without departing from the spirit andscope of the invention illustrated and described herein.

What is claimed is:

1. A reed dent arrangement for a wave-motion loom wherein the reed dentsare arranged between laminar guide elements, are of elongatelamella-like shape, and travel at one narrow side on a drive cammingmeans due to which there are imparted to them. a rocking movement whichtakes place about a pivot extending perpendicular to their broad sides,characterized in that each reed dent has at least at one location athickened portion which bears on said drive camming means and saidpivot, and in those zones over which the thickened portions extend andover which they travel, the guide elements are formed with recesses.

2. The reed dent arrangement according to claim 1 in which saidthickened portion is constituted by an elongate element secured to thereed dent and extending along its longitudinal edge which passes intoabutment.

3. The reed dent arrangement according to claim 2 in which saidthickened portion is constituted by a strip-shaped element secured to alateral face of said reed dent.

4. The reed dent arrangement according to claim 3 in which the thickenedportion is constituted by an elongate, narrow, U-shaped element securedto said reed dent.

5. The reed dent arrangement according to claim 1 in which each reeddent has a thickened portion at all locations at which it bears on thedrive camming means.

6. The reed dent arrangement according to claim 1 in which saidthickened portions bearing on said drive camming means have a width atleast equal to the maximum rocking of directly adjacent reed dentsrelative to each other at the location of the end adjacent the pivot ofthe said thickened portions.

7. The reed dent arrangement according to claim 1 in which, in the caseof thickened portions provided at the location of abutment of the reeddent at the pivot, a maximum minimal interspace is provided for maximumallowable play.

8. The reed dent arrangement according to claim 7, for a rocking shaftloom, wherein the drive camming means is disposed on one of the narrowsides of the reed dent, characterized in that each of the reed dentsbears in a recess at the pivot which is located on the narrow side ofthe reed dent opposite the camming means and which at maximum halfembraces the pivot.

1. A reed dent arrangement for a wave-motion loom wherein the reed dents are arranged between laminar guide elements, are of elongate lameLla-like shape, and travel at one narrow side on a drive camming means due to which there are imparted to them a rocking movement which takes place about a pivot extending perpendicular to their broad sides, characterized in that each reed dent has at least at one location a thickened portion which bears on said drive camming means and said pivot, and in those zones over which the thickened portions extend and over which they travel, the guide elements are formed with recesses.
 2. The reed dent arrangement according to claim 1 in which said thickened portion is constituted by an elongate element secured to the reed dent and extending along its longitudinal edge which passes into abutment.
 3. The reed dent arrangement according to claim 2 in which said thickened portion is constituted by a strip-shaped element secured to a lateral face of said reed dent.
 4. The reed dent arrangement according to claim 3 in which the thickened portion is constituted by an elongate, narrow, U-shaped element secured to said reed dent.
 5. The reed dent arrangement according to claim 1 in which each reed dent has a thickened portion at all locations at which it bears on the drive camming means.
 6. The reed dent arrangement according to claim 1 in which said thickened portions bearing on said drive camming means have a width at least equal to the maximum rocking of directly adjacent reed dents relative to each other at the location of the end adjacent the pivot of the said thickened portions.
 7. The reed dent arrangement according to claim 1 in which, in the case of thickened portions provided at the location of abutment of the reed dent at the pivot, a maximum minimal interspace is provided for maximum allowable play.
 8. The reed dent arrangement according to claim 7, for a rocking shaft loom, wherein the drive camming means is disposed on one of the narrow sides of the reed dent, characterized in that each of the reed dents bears in a recess at the pivot which is located on the narrow side of the reed dent opposite the camming means and which at maximum half embraces the pivot. 